The present invention relates to an electrophoresis analyzer with wavelength selective detection and more particularly to an electrophoresis analyzer with wavelength selective detection which is suited to an electrophoresis analysis apparatus for DNA, RNA, or protein.
To analyze DNA, a method for labeling a sample by a fluorophore and optically detecting and analyzing the sample which is electrophoretically separated is used. To compare and analyze various types of samples or increase the throughput of analysis, it is necessary to label a plurality of types of samples respectively by using a plurality of fluorophores with different light emitting wavelengths as labeling fluorophores and to separate and analyze a plurality of types of samples at the same time. In this case, it is necessary to separate and detect the wavelength of fluorescence from each fluorophore. However, generally by using a color filter wheel having a plurality of filters through which light with a predetermined wavelength can transmit, the wavelength of fluorescence is separated and measured (Nature, 1986, Vol. 321, p. 674).
A conventional gel electrophoresis plate is about 20 cm.times.40 cm in size and has a linear fluorescence emitting region perpendicular to the electrophoretic direction, which is 10 to 15 cm in length. As a method for efficiently detecting fluorescence from such a linear fluorescence emitting region, a method for using a two-dimensional detector and image splitting prism is proposed (U.S. Pat. No. 5,062,942). This method makes a plurality of images of the fluorescence emitting region which are split vertically using a prism or mirror and focusing lens on the detection surface of the two-dimensional detector. Each image is devised so as to be formed on the detection surface after passing through a filter installed in each optical path and wavelength-separated fluorescence images can be detected.
A capillary array electrophoresis method has been proposed recently as an electrophoresis method for separating and analyzing various types of samples (U.S. Pat. No. 5,277,780). The method is designed to line up many capillaries so as to measure samples and is suited to high-speed and high-throughput measurement. According to this method, the inner diameter and inner gel are slightly different in each capillary, so that the electrophoretic speed is changed even in the same sample. Therefore, it is necessary to determine a molecular weight standard by migrating a marker labeled with a fluorophore different from the fluorophore which is labeled for each sample at the same time.